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51.
Yoshio Kawai Teruyuki Fujita Shozo Koga 《Bioscience, biotechnology, and biochemistry》2013,77(8):1799-1802
Ribosomal particles of E. coli were examined by using a heat leakage scanning calorimeter. Remarkable changes were observed in thermograms of 70S ribosomes and their subunits when the Mg2+ concentration was raised from 1 mm to 10 mm. It was suggested that ribosomal subunits exist in more than one conformation, and changes in their conformation might be the primary cause of the association-dissociation process of ribosomes. Comparisons of thermograms of RNase- and chymotrypsin-treated, as well as non-treated SOS and 30S subunits suggest that conformational changes in each subunit may be ascribed to changes in rRNA. 相似文献
52.
Tatsuyoshi Kobayashi Yoshio Sakai Shinobu Mutoh 《Bioscience, biotechnology, and biochemistry》2013,77(6):378-386
The purpose of this study is to find optimal conditions for pre-hydrolysis in the new wood saccharification process with strong sulfuric acid. In the experiment, the hydrolysis rate of resistant fraction of pentosan of white birch (Shirakamba, Betula platyphylla Sukatchev var. japonica Hara) wood and the decomposition rate of xylose are measured in acid concentrations ranging from 30 to 60% at temperatures ranging from 30 to 90°C. The hydrolysis of resistant pentosan of white birch and the decomposition of xylose are the first-order reactions. The first-order reaction constant of hydrolysis of resistant pentosan, kB min-1, is expressed by the following empirical equations as the function of percentage concentration of sulfuric acid, C, and reaction temperature described by absolute temperature, T°K, ranging from 40 to 80°C: where sulfuric acid concentrations range from 30 to 50%; where sulfuric acid concentration is 60%.The first-order reaction constant of decomposition of xylose, k2 min-1, is expressed by the following empirical equation as the function of sulfuric acid strength described by acidity function, H0, and reaction temperature described by absolute temperature, T°K, in sulfuric acid concentrations ranging from 30 to 60% at temperatures within the range of 40 to 100°C. where C is sulfuric acid strength described by acidity function, H0. 相似文献
53.
Kei Arima Teiiti Narasaki Yoshio Nakamura Gakuzo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(8):924-929
About 2000 strains of microorganisms were examined for lipoprotein lipase producibilities and some microorganisms were found to produce lipases similar to animal lipoprotein lipases.Microorganisms were cultured on solid media containing a serum-activated olive oil emulsion, and strains which formed a clear zone around the colony were collected. The collected microorganisms were cultured on liquid media containing 0.5% of olive oil by shaking and the culture filtrates were tested for lipoprotein lipase activity by a turbidity method. The superior lipoprotein lipase producers obtained belonged to genera of Serratia, Pseudomonas, Mucor, and Streptomyces. 相似文献
54.
Ayaaki Ishizaki Hiroshiro Shibai Yoshio Hirose Teruo Shiro 《Bioscience, biotechnology, and biochemistry》2013,77(1):107-113
In inosine fermentation, the yield of the product was closely related to the partial pressure of carbon dioxide in the culture system rather than the bicarbonate ion concentration in the culture liquid. The inhibitory effect of carbon dioxide was restored by the methods of reducing the partial pressure of carbon dioxide lower than a certain level. Both ventilation and chemical absorption were applicable for the restoration of the carbon dioxide inhibition, but ventilation had great advantages over the other method from an industrial view-point. In the estimation of aeration-agitation conditions for the scale-up of submerged fermentation in which carbon dioxide was inhibitory, the rate of aeration was to be established to make sufficient ventilation and overcome this inhibition. A scheme for the procedure for the estimation of aeration-agitation conditions under the consideration of influences of carbon dioxide on submerged fermentation was proposed in this paper. 相似文献
55.
Noboru Murofushi Yoshio Shigematsu Shigehiro Nagura Nobutaka Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(9):2305-2311
Steviol (ent-13-hydroxykaur-16-en-19-oic acid)* is metabolized by Gibberella fujikuroi in the presence of inhibitors of gibberellin biosynthesis, such as quaternary ammonium salt-type growth retardants, to afford 7β-Miydroxy- and 6β,7β-dihydroxysteviol, gibberelhns A1, A18, A19, A53 and 7β,13-dihydroxykaurenolide. Steviol acetate (ent-13-acetoxykaur-16-en-19-oic acid) is also metabolized to the 6β,7β-dihydroxy-derivative and to the 13-acetyl derivatives of gibberellins A17 and A20 and steviol methyl ester (methyl ent-13-hydroxykaur-16-en-19-oate) into the monohydroxy-, dihydroxy- and hydroxyoxo-derivatives. These results indicate a low substrate specificity of the enzymes in the fungus and provide a useful preparative methodology of several important plant gibberellins carrying the 13-hydroxyl group. 相似文献
56.
57.
Yoshio Hirose Hiroshi Sonoda Kazumoto Kinoshita Hiroshi Okada 《Bioscience, biotechnology, and biochemistry》2013,77(6):585-593
The unsteady-state gas analysis method for the determination of oxygen transfer rate in shaken cultures was applied to the glutamic acid fermentation. This method was essentially based on the measurement of oxygen tension of gas phase in flasks. Major intentions of this application were to clarify the problems of oxygen transfer, to establish the measure of aeration effectiveness and to design the best aeration condition in the glutamic acid fermentation. Correlations of the fermentation to the level of dissolved oxygen, the rate of oxygen transfer, overall oxygen transfer coefficient and oxygen demand of cells were examined. As a measure of aeration effectiveness, the rate of oxygen transfer actually occurring in the fermentation seemed to be preferable, and was found to be above 7 × 10?7 mol/ml-min for attaining the maximum productivity. Extremely high or low oxygen supply resulted in less productivity. 相似文献
58.
Yoshio Ozawa Shunro Kawakishi Yasushi Uda Yasuhiko Maeda 《Bioscience, biotechnology, and biochemistry》2013,77(5):1241-1245
The methanol extract of salted radish roots contains several precursors of yellow pigment. The main compound was isolated by the use of Toyopearl HW-40S column chromatography, and its structure was determined to be 1-(2′-pyrrolidinethion-3′-yl)-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid on the basis of an elemental analysis, and IR, UV, FAB-MS and NMR spectroscopy. This compound is presumed to have been the condensation product from the degradation of 4-methylthio-3-butenyl isothiocyanate and l-tryptophan. This carboline compound is considered to play an important role in the formation of the yellow pigment in salted radish roots. 相似文献
59.
60.
Yuji Enomoto Yoshio Furutani Hiroshi Naganawa Masa Hamada Tomio Takeuchi Hamao Umezawa 《Bioscience, biotechnology, and biochemistry》2013,77(7):1331-1336
In the screening for inhibitors of cyclic adenosine-3′,5′-monophosphate phosphodiesterase, two compounds, PDE-I (C13H13N3O5) and PDE-II (C14H14N2O5), were isolated from culture filtrates of a Streptomyces. Concentrations for 50% inhibitions of PDE-I and PDE-II against the high Km enzyme were 15 µm and 13 µm, and those against the low Km enzyme were 65 µm and 130 µm, respectively. Production, isolation and characterization of these compounds are described. 相似文献